Hydroentangling or spunlacing is a technique introduced during the 1970's, see e.g. CA patent no. 841 938. The method involves forming a fiber web which is either drylaid or wetlaid, after which the fibers are entangled by means of very fine water jets under high pressure. Several rows of water jets are directed against the fiber web which is supported by a movable wire. The entangled fiber web is then dried. The fibers that are used in the material can be synthetic or regenerated staple fibers, e.g. polyester, polyamide, polypropylene, rayon or the like, pulp fibers or mixtures of pulp fibers and staple fibers. Spunlace materials can be produced in high quality to a reasonable cost and have a high absorption capacity. They can e.g. be used as wiping material for household or industrial use, as disposable materials in medical care and for hygiene purposes etc.
Through e.g. EP-A-0 333 211 and EP-A-0 333 228 it is known to hydroentangle a fiber mixture in which one of the fiber components is meltblown fibers. The base material, i.e. the fibrous material which is exerted to hydroentangling, either consists of at least two preformed fibrous layers where one layer is composed of meltblown fibers or of a “coform material” where an essentially homogeneous mixture of meltblown fibers and other fibers is airlaid on a wire and after that is exerted to hydroentangling.
Through EP-A-0 308 320 it is known to bring together a web of continuous filaments with a wetlaid fibrous material containing pulp fibers and staple fibers and hydroentangle together the separately formed fibrous webs to a laminate. In such a material the fibers of the different fibrous webs will not be integrated with each other since the fibers already before the hydroentangling are bonded to each other and only have a very limited mobility.
EP-A-0 938 601 discloses a method of producing a nonwoven material by hydroentangling a fiber mixture containing continuous filaments, e.g. meltblown and/or spunbond fibers, and other fiber. The method is characterized by foamforming a fibrous dispersion of natural fibers and/or synthetic staple fibers and hydroentangling together the foamed fiber dispersion with the continuous filaments for forming a composite material, in which the continuous filaments are well integrated with the rest of the fibers.
One problem arising from that different process units are used for laying the continuous filaments and the fibrous dispersion of natural fibers and/or synthetic staple fibers, wherein the handling and transfer of the formed web components between the different process components is very sensitive and critical in order not to disturb the formed web components. A web of unbonded continuous filaments is very fluffy and tears very easily if disturbed by for example air streams or water streams.